BOSTON, Massachusetts (CNN) -- Former presidential candidate Howard Dean said Tuesday that the Democratic Party is united in its opposition to President Bush and that the convention is Sen. John Kerry's week to shine.

The former Vermont governor is scheduled to speak Tuesday evening at the Democratic National Convention but declined to give reporters a preview, saying, "You're going to find out at 9 o'clock tonight."

Amid talk of rhetoric being toned down for this week's convention, Dean said the Kerry campaign did not vet his speech because it was written by two former speechwriters for the presumptive Democratic nominee.

"This is the most unified party I have seen in seven conventions," Dean said. "I've been to every convention since 1980, and I have never seen the party like this. We really are pretty much unified in common purpose.

"There are not a lot of differences, and [the] differences we have are so small compared to differences between us and George Bush that we're very willing to put aside those differences."

He added, "We're all together because we believe that George Bush is serving America very badly with weak leadership, weak national defense, weak on financial matters -- half-trillion dollar deficits, loss of jobs. This president has been a disaster for America."

Dean said Kerry's task now is to get voters who oppose Bush to support him.

"This is John Kerry's week to shine. This is John Kerry's week to tell his story to the American people. That's why we want to stay positive," he said.

Dean answered questions after speaking to a breakfast hosted by the New York delegation.

"We as Democrats did not to stand up to this right-wing administration when we should have stood up to them -- which was the day after inauguration," the one-time candidate said in remarks reminiscent of his campaign.

"One thing I discovered on the campaign trail is that 95 percent of Americans want exactly the same thing -- jobs, health care, better public schools system and national security.

"Sooner or later, the people from these states that vote 65 percent Republican are going figure out that they vote for the right-wingers who forget them as soon as they cross the border on the way to Washington, D.C."

But Dean said he didn't think liberalism is dead. "I think that I represented the centrist wing of the party when I ran -- balanced budgets, death penalty support in some instances, eight consecutive A's from the National Rifle Association," he said.

"I think the biggest problem with the Democrats is they didn't realize how far to the right the country really went. So, I think we're all centrists. We believe in balanced budgets; the president believes in huge debts."

In foreign policy, he said, the United States has "lost the moralistic leadership in the world."

Dean said he would be working to push progressive activists in "safe" Democratic states to help the ticket in battleground states.

"I think New York is pretty safe territory for Kerry and [John] Edwards, but I want to make sure New Yorker folks play an instrumental role in other states," he said.

"What we're going to try to do in California, for example, which is another state we feel pretty confident about, is have Californians go to Arizona, New Mexico, to Oregon and Nevada ...," Dean said. "We'd like to get some New York folks to send some volunteers to places like Pennsylvania and Ohio, which are going to be critical states for us."